Improved emulsifying properties of water-soluble myofibrillar proteins at acidic pH conditions: Emphasizing pH-regulated electrostatic interactions with chitosan

作者：Huang, Mingyuan; Xu, Yujuan; Chen, Xing; Xu, Lina; Bai, Yun; Xu, Xinglian^*; Zeng, Xianming

来源：International Journal of Biological Macromolecules, 2024, 257: 128557.

DOI：10.1016/j.ijbiomac.2023.128557

• Water-soluble myofibrillar proteins
• Electrostatic interactions
• pH
• Emulsion stability
• Chitosan

Water-soluble muscle protein with enhanced functionalities has attracted great interest for low-salt food design. Electrostatic interactions of chitosan (CS) with myofibrillar proteins (MP) in water-aqueous solution at acidic pHs (4.0-6.5) were investigated, and how pH regulated complex formation, microstructures, conformation changes, and emulsifying capacity was systematically explored. At pH 4.0-4.5, MP and CS were positively charged and displayed a co-soluble system, exhibiting small particles and high solubility. When the pH increased to near the isoelectric point (pI) of MP (pH 5.0-6.0), electrostatic interactions largely inhibited the aggregation of MP by forming smaller particle complexes. The flexible structures and improved amphiphilic properties promoted protein absorption at the oil-water interface, further improving the emulsion stability. When the pH increased to 6.5, large aggregates were formed causing poor functionalities. This study could provide great insights to further exploit meat-protein-based low-salt functional foods in novel food design.

• 单位
  南京农业大学; 江南大学